摘要
为避免高温钎焊条件下钎料与TiAl母材发生过度反应,设计了CoFe基和Fe基两种高温钎料。在1100℃/10min和1200℃/10min条件下进行了钎料对TiAl合金的润湿性实验,在1180℃/5min条件下进行TiAl合金的真空钎焊实验。结果表明,1200℃/10min条件下两种钎料在TiAl合金上润湿角约为30°。与Ni基钎料相比,两种钎料与TiAl的界面反应程度得到缓解。CoFe基钎料对应接头界面主要形成Ti3Al,TiAl,硅化物和(Ti,Cr)-B,而在宽度较窄的(约10μm)钎缝中心形成了富Cr固溶体。Fe基钎料接头组织基本与CoFe基钎料接头类似,区别在于钎缝中心为残余钎料区,宽度约40μm,主要为Fe基固溶体。残余钎料区附近生成TiB和TiB2两种硼化物,与CoFe基钎料接头中硼化物相比,数量明显增多。
CoFe-based and Fe-based high-temperature filler metals were studied for the control of the excessive reaction between filler metal and TiAl base metal at high brazing temperatures.The wett-ability of two filler metals on TiAl was studied at 1100℃/10min and 1200℃/10min,and the vacuum brazing experiment was carried out at 1180℃ for 5min.The results showed that the contact angles of the two kinds of filler metals were about 30° at 1200℃/10min.The interfacial reactions of the two filler metals with TiAl were not as strong as that of the traditional Ni-based filler metal.Main microstructures of the joint brazed with CoFe-based filler metal were Ti3Al,TiAl,silicide and（Ti,Cr）-B phase.Furthermore,a narrow Cr-rich solid solution zone（about 10μm） was formed in the central part of the joint.The similar microstructures were formed for the joint brazed with Fe-based filler metal.But there is also a difference,for the joint brazed with Fe-based filler metal,a wider residual filler metal zone（about 40μm） was formed in its central part,and the main phase was identified to be Fe-rich solid solution.TiB and TiB2 phases were formed near the residual filler metal zone,and the amount of borides was much more than that of CoFe-based filler metal.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2010年第10期61-64,68,共5页
Journal of Materials Engineering
基金
预研基金项目(9140A180501HK5105)
关键词
高温钎料
TIAL
显微组织
high-temperature filler metal
TiAl
microstructure
